Title: Re: Fukushima 50000 Bq/kg Cesium found in Monkey turds
Post by Bojack Horseman on Mar 7th, 2016 at 3:09pm
Possible benefits[edit]
Early thorium-based (MSR) nuclear reactor at Oak Ridge National Laboratory in the 1960s
The World Nuclear Association explains some of the possible benefits[16]
The thorium fuel cycle offers enormous energy security benefits in the long-term – due to its potential for being a self-sustaining fuel without the need for fast neutron reactors. It is therefore an important and potentially viable technology that seems able to contribute to building credible, long-term nuclear energy scenarios.[17]
Moir and Teller agree, noting that the possible advantages of thorium include "utilization of an abundant fuel, inaccessibility of that fuel to terrorists or for diversion to weapons use, together with good economics and safety features … "[4] Thorium is considered the "most abundant, most readily available, cleanest, and safest energy source on Earth," adds science writer Richard Martin.[15]:7
Thorium is three times as abundant as uranium and nearly as abundant as lead and gallium in the Earth's crust.[18] The Thorium Energy Alliance (TEA) estimates "there is enough thorium in the United States alone to power the country at its current energy level for over 1,000 years."[17][18] "America has buried tons as a by-product of rare earth metals mining," notes Evans-Pritchard.[19] Almost all thorium is fertile Th-232, compared to uranium that is composed of 99.3% fertile U-238 and 0.7% more valuable fissile U-235.
It is difficult to make a practical nuclear bomb from a thorium reactor's byproducts. According to Alvin Radkowsky, designer of the world's first full-scale atomic electric power plant, "a thorium reactor's plutonium production rate would be less than 2 percent of that of a standard reactor, and the plutonium's isotopic content would make it unsuitable for a nuclear detonation."[15]:11[20] Several uranium-233 bombs have been tested, but the presence of uranium-232 tended to "poison" the uranium-233 in two ways: intense radiation from the uranium-232 made the material difficult to handle, and the uranium-233 led to possible pre-detonation. Separating the uranium-232 from the uranium-233 proved very difficult, although newer laser techniques could facilitate that process.[21][22]
There is much less nuclear waste—up to two orders of magnitude less, states Moir and Teller,[4] eliminating the need for large-scale or long-term storage;[15]:13 "Chinese scientists claim that hazardous waste will be a thousand times less than with uranium."[19] The radioactivity of the resulting waste also drops down to safe levels after just a few hundred years, compared to tens of thousands of years needed for current nuclear waste to cool off.[23]
According to Moir and Teller, "once started up [it] needs no other fuel except thorium because it makes most or all of its own fuel."[4] This only applies to breeding reactors, that produce at least as much fissile material as they consume. Other reactors require additional fissile material, such as uranium-235 or plutonium.[17]
Thorium fuel cycle is a potential way to produce long term nuclear energy with low radio-toxicity waste. In addition, the transition to thorium could be done through the incineration of weapons grade plutonium (WPu) or civilian plutonium.[24]
Since all natural thorium can be used as fuel no expensive fuel enrichment is needed.[23] However the same is true for U-238 as fertile fuel in the uranium-plutonium cycle.
Comparing the amount of thorium needed with coal, Nobel laureate Carlo Rubbia of CERN, (European Organization for Nuclear Research), estimates that one ton of thorium can produce as much energy as 200 tons of uranium, or 3,500,000 tons of coal.[25] Coal, makes up 42% of U.S. electrical power generation and 65% in China.[26]
Liquid fluoride thorium reactors are designed to be meltdown proof. A plug at the bottom of the reactor melts in the event of a power failure or if temperatures exceed a set limit, draining the fuel into an underground tank for safe storage.[27]
Mining thorium is safer and more efficient than mining uranium. Thorium's ore monazite generally contains higher concentrations of thorium than the percentage of uranium found in its respective ore. This makes thorium a more cost efficient and less environmentally damaging fuel source. Thorium mining is also easier and less dangerous than uranium mining, as the mine is an open pit which requires no ventilation, unlike underground uranium mines, where radon levels can be potentially harmful.[28]
Summarizing some of the potential benefits, Martin offers his general opinion: "Thorium could provide a clean and effectively limitless source of power while allaying all public concern—weapons proliferation, radioactive pollution, toxic waste, and fuel that is both costly and complicated to process.[15]:13 From an economics viewpoint, UK business editor Ambrose Evans-Pritchard has suggested that "Obama could kill fossil fuels overnight with a nuclear dash for thorium," suggesting a "new Manhattan Project," and adding, "If it works, Manhattan II could restore American optimism and strategic leadership at a stroke …"[25] Moir and Teller estimated in 2004 that the cost for their recommended prototype would be "well under $1 billion with operation costs likely on the order of $100 million per year," and as a result a "large-scale nuclear power plan" usable by many countries could be set up within a decade.[4]
And my work is done
*drops mike, exits stage left*
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